Minneapolis, MN, May 14, 2013 – BioAmber Inc. (“BioAmber”) (NYSE: BIOA.U),
announced today the closing of its initial public offering of 8,000,000 units consisting of one share
of common stock and one warrant to purchase half of one share of common stock at $10.00 per
unit, before underwriting discounts and commissions. Each warrant will be exercisable at an
exercise price of $11.00 per whole share of common stock. All units are being sold by BioAmber.
The units are listed on the New York Stock Exchange (“NYSE”) under the symbol “BIOA.U”. The
common stock and warrants comprising the units will begin trading separately on NYSE under the
symbols “BIOA” and “BIOA.WS”, respectively, on Monday, June 10, 2013 at which time trading
of the units will be suspended and the units will be delisted. BioAmber also intends to list its
common stock on the Professional Segment of the regulated market of NYSE Euronext in Paris under
the symbol “BIOA.”

Credit Suisse, Barclays and Société Générale are acting as joint book-running managers for the
offering. Pacific Crest Securities is acting as co-manager for the offering.

A registration statement relating to these securities has been filed with, and declared effective by,
the U.S. Securities and Exchange Commission on May 9, 2013. This press release shall not
constitute an offer to sell or the solicitation of an offer to buy, nor shall there be any sale of these
securities in any state or jurisdiction in which such offer, solicitation or sale would be unlawful prior
to registration or qualification under the securities laws of any such state or jurisdiction.

The offering of these securities was made only by means of a prospectus, copies of which may be
obtained from Credit Suisse Securities (USA) LLC by mail at One Madison Avenue, New York,
New York 10010, Attention: Prospectus Department, or by calling toll free (800) 221-1037, or by
emailing newyork.prospectus@credit-suisse.com.

About BioAmber Inc.

BioAmber is a next generation chemicals company. Its proprietary technology platform combines
industrial biotechnology and chemical catalysis to convert renewable feedstocks into chemicals
including succinic acid and 1,4-butanediol, which are used in a wide variety of everyday products
such as plastics, food additives and personal care products. For more information visit the
company’s web site at: www.bio-amber.com.

Forward-Looking Statements

This press release contains forward-looking statements, which are subject to substantial risks,
uncertainties and assumptions. These statements often include words such as “believe,” “expect,”
“anticipate,” “intend,” “plan,” “estimate,” “seek,” “will,” “may” or similar expressions. Although
we believe that the expectations reflected in the forward-looking statements are reasonable, we
cannot guarantee that the events and circumstances reflected in the forward-looking statements will
be achieved or occur and the timing of events and circumstances and actual results could differ
materially from those projected in the forward- looking statements. Accordingly, you should not
place undue reliance on these forward-looking statements. All such statements speak only as of the
date made, and we undertake no obligation to update or revise publicly any forward-looking
statements, whether as a result of new information, future events or otherwise.